1. Field of the Invention
The invention relates to a process for consolidating beds of particulate solids that include some water into unitary porous solids. The invention also relates to various useful cleaning products, especially to textile, dishwashing, and surface care cleaning products in porous solid form, which can be made by the process. Still another aspect of the invention relates to using the novel solid detergents, cleaners, soaps and surface care products.
A product according to this invention is a "macrosolid", i.e., it is a unitary solid three dimensional object that is (i) capable, at a minimum, of retaining a definite shape and size under the influence of the normal ambient gravitational field at the surface of the earth and of being moved as a unit by forces exerted at only one end or edge thereof and (ii) sufficiently large to include within itself at least one hypothetical cube having a length of 2.5 millimeters (hereinafter often abbreviated "mm") on each edge. Preferably, with increasing preference in the order given, a macrosolid product according to the invention is sufficiently large to include within a single product a hypothetical cube having a length of 5, 6.5, 8.2, 10.0, 12.1, or 13.0 mm on each edge. A macrosolid thus contrasts with a conventional granular or powdered solid material, in which each unitary particle is normally no more than 2.2 mm in at least one of its three principal geometric dimensions. (Granular or powdered solid cleaners are often preferred for domestic use, where the amount of cleaning power required often is highly variable from one use of the cleaner to the next. However, granular or powdered cleaners require the performance of a separate volume or mass measuring step in order to give reproducible results and efficient use of the cleaner. Therefore, under industrial or other conditions where the amount of cleaning power needed from one use of a cleaner to the next is fairly constant, and/or the value of time saved is more economically important than the possible waste of small amounts of cleaner, macrosolid cleaners are generally preferred, because a worker can quickly select and use some small integral number, usually one, of the macrosolid cleaners for each instance of use, without the need for any more time-consuming measurement step.)
The units of the macrosolid cleaner according to this invention are commonly called "tablets" or "blocks", and these terms are used herein for convenience in description but are not to be understood in and of themselves to imply anything about the content, strength, or application of the particular formulation. Smaller macrosolids on the order of 10 to 50 grams in mass are generally referred to as "tablets" because such relatively small macrosolids often are cylinders with a height substantially less than the diameter, while larger macrosolids with masses on the order of 100 grams (hereinafter often abbreviated "g") to several kilograms (hereinafter often abbreviated "kg") are generally referred to as "blocks". Unless explicitly further qualified, however, neither "tablet" or "block" should be understood herein as having any quantitative implications.
2. Discussion of Related Art
Acidic to strongly alkaline cleaners and detergents find wide application in the form of powders, granulates, tablets, pastes, and blocks. Tablets and blocks in the prior art have generally been made by pressing of powdered solids or of paste-like slurries of such solids, or by molding of molten constituents or of slurries of partially solid constituents in some liquid that readily fills a mold. Many prior art processes for the production of solid cleaning products or molded cleaners, for example, require heating and mixing of the raw materials and/or aqueous solutions in order to insure homogeneity in the final product. In addition, thickening, pouring, and cooling of the heated mixtures either alone or with the use of molds or forms may also be required.
Most conventional prior art techniques for the production of tablets or molded cleaners suffer from the disadvantage that they require the addition of certain additional auxiliaries, such as tabletting aids, which must be added to the cleaning-effective raw materials. These aids are required in order to stabilize the active ingredients to form a slurry or paste mixture for further processing such as melting, pouring or being pressed into the final desired product form. Such auxiliaries add no cleaning power or other desired properties to the final product, but yet are often required to enable raw materials to be conveniently pumped or otherwise conveyed within a process, or to facilitate heat transfer where raw materials exhibit different degrees of heat stability. The use of such auxiliaries may also contribute to delivery and dissolving problems. The use of tabletting aids also is disadvantageous because it increases both raw materials and manufacturing costs.